Numerical Simulation Study Of Mesoscopic And Macro-Mesoscopic Coupling Of Pbx Crack Propagation

Polymer Bonded Explosives(PBX)is the key material for weapons killing,destruction,and power energy.Modern weapon systems are developing rapidly.As an important part of PBX,its security issues are very important.PBX damage,The study of mechanical properties such as fractures has also received more and more attention.It is necessary to proceed from multiple angles and comprehensively use theories,experiments,and numerical simulations to conduct related research.Macroscopic and microscopic coupled numerical simulation is the macroscopic response and mesomechanism of the connecting materials.Effective means,therefore,the study of the mesoand macro-mechanical coupling angles of polymer binder explosives is of great significance to the exploration of their mechanical properties.The main research object of this article is PBX explosives.In this paper,the constitutive relationship and crack propagation criterion of PBX explosives are first studied,and the numerical simulation of crack propagation of PBX components using the extended finite element method is confirmed.According to the actual mesostructure of PBX materials under the light microscope,the program is written through the matlab platform.The Voronoi model and the random particle model are established,and then the meticulous finite element model of the structure generated by the finite element software is imported through the Python language.Secondly,the crack propagation behavior of explosives was numerically simulated by using the mesoscopic finite element model of the PBX material established above,and the effects of different mesostructures,loading forms,particle content,etc.on the mechanical behavior of PBX materials were analyzed,and cracks in the PBX meso-model were obtained.Expand the law.Finally,the macroscopic and macroscopic coupling model of PBX explosive threepoint bending beam,three-point bending arch and Brazilian disk test was established.The crack propagation behavior during the deformation process was numerically simulated by the extended finite element method to obtain the PBX macroscopic and The crack propagation law of macroscopically coupled model and the critical load of fracture failure compare the fracture characteristics of the two types of models and further elucidate the importance of mesostructure on the macroscopic properties of PBX explosives.